This invention relates to tubular skylight assemblies, for example, of the general type disclosed in U.S. Pat. Nos. 6,219,977, 6,256,947, and Reissue No. 36,496. Such tubular skylights are commonly installed within the attic of a home and extend from an inclined roof to a flat horizontal ceiling and usually include a cylindrical light conducting tube which may be flexible and collapsible or formed of rotatably connected cylindrical tube sections. The upper open end portion of the tube is covered by a light transmitting skylight usually formed of a plastics material and having an outwardly projecting flange which projects under the roof covering or shingles. The lower open end of the tubing is commonly covered by a light transmitting plastic panel or lens which is attached to the ceiling by a frame. The flexible and collapsible light conducting tube is sometimes constructed of an extruded plastic film surrounding a helically wound wire for accommodating the horizontally offset or angular condition between the inclined roof rafters and the horizontal ceiling joists.